Conservation Column: Springfield’s LED Street Lights
As many of you are aware, streetlights can negatively impact the health and welfare of both humans and birds. New streetlights purchased by the city of Springfield seem likely to exacerbate those impacts.
What’s the problem?
Impacts on people include:
•Disruption of circadian rhythms. The light, especially the blue light, interferes with the natural production of melatonin, a hormone which regulates our natural daily rhythms. Interference with circadian rhythms causes sleep disruption which, in turn, increases sleepiness and decreases alertness during the day. Research suggests that an increase in certain diseases may be associated with artificial lighting at night.
•Light pollution obstructs our ability to view the night sky. According to the International Dark Sky Association, 4000Kelvin LED lights more than double light pollution.
•LED lights increase glare, constricting the pupils and interfering with our ability to see, especially in the aging eye. This increases the risk of automobile and pedestrian accidents. Many compare LED light to a car heading toward you with its brights on.
Impacts on birds include:
•Migration: River ways are the most common corridor used by migrating birds. The City of Springfield, with its proximity to two rivers, is important to migratory birds on the Northwest flyway. Even typically diurnal birds, such as songbirds, actually migrate during the night. The birds become disoriented by lights, especially when they shine upward. City lights often attract birds away from their migration path, and since their usual navigation aids are obscured, they have a difficult time finding their way back. Once in the city, they are more vulnerable to harm, where they die by the millions each year from collisions with buildings. Some birds will circle over lighted areas, become fatigued and fall to the ground where they are easy prey for predators.
•Disruption of circadian rhythms. The disruption of circadian rhythms in birds has many of the same effects as in people. In addition, several scientific studies have found additional adverse behavioral and physiological effects. Males near streetlights start singing earlier in the morning; females lay eggs days or weeks earlier than normal. An increase in stress hormones and a decrease in immune function have been documented when birds are exposed to artificial lighting. Birds exposed to LED lights sleep less, wake earlier, and leave nest boxes more often.
Statement from the American Medical Association (AMA):
“Recognizing the detrimental effects of poorly-designed, high-intensity LED lighting, the AMA encourages communities to minimize and control blue-rich environmental lighting by using the lowest emission of blue light possible to reduce glare. The AMA recommends an intensity threshold for optimal LED lighting that minimizes blue-rich light. The AMA also recommends all LED lighting should be properly shielded to minimize glare and detrimental human health and environmental effects, and consideration should be given to utilize the ability of LED lighting to be dimmed for off-peak time periods.”
Recently the City of Springfield installed LED streetlights downtown with plans to install more at a later date. We are not opposed to installation of responsible street lighting in Springfield to create a safe and welcoming area, and to do so in a cost-conscious manner. But we ask that action be taken to decrease known problems associated with LED lights. The city had purchased several of the LED streetlights (most are still in storage) at a bargain price from San Diego. There’s a reason those lights were such a bargain. They were no longer suitable under the 2012 San Diego ordinance, which minimizes negative impacts (including glare and urban sky glow) from outdoor light fixtures. People across the nation are demanding that their cities install more friendly lighting, and cities are responding with appropriate ordinances. The Springfield streetlights, which are not shielded, are rated at 4000K, which is above the acceptable level (less than or equal to 3000K) suggested by most research. One of the problems with this type of light is that, although it appears white to our eyes, it emits a significant amount of light in the blue spectrum. LED lights, especially those that emit strongly in the blue portion of the spectrum, have been shown to cause more glare and be a more powerful disruptor of circadian rhythms than other kinds of lights.
What’s the solution?
No matter what municipality you live in, educate decision makers about the negative impacts of high intensity, unshielded LED lights, and insist that they install acceptable lights. Bend, Eugene, and Portland all have protective ordinances.
Monitor your own lights. Turn off unnecessary outside lights (especially floodlights) and be sure they are shielded, directed downwards and away from neighbors. Use lights with the lowest possible Kelvin rating that emit the least amount of light in the blue spectrum. Use window coverings to block light coming from inside the house.
Recommendations for actions on the Springfield lighting project:
Request that, in the future, the city install streetlights that are less than 3000K, are directed to shine only downward, and have proper shielding to prevent glare.
For the lights already in place:
•Retrofit with proper shielding to keep light focused downward.
•Keep dimmed at all times to less than 3000K output.
•Lights out or maximally dimmed, especially during spring and fall migration season, late in the evening when shops have closed but birds are migrating.
Contact the Springfield City Manager and Springfield City Councilors and request these actions.
City Councilors contact info: springfield-or.gov/council.htm
City Manager Gino Grimaldi, firstname.lastname@example.org, or 541.726.3700
Monitor your own lights: Turn off unnecessary outside lights (especially floodlights) and be sure they are shielded, directed downwards and away from neighbors. Use lights with the lowest possible Kelvin rating that emit the least amount of light in the blue spectrum. Use window coverings to block light coming from inside the house.